Physics-
General
Easy
Question
In a Young's double slit experiment, green light is incident on the two slits. The interference pattern is observed on a screen. Which of the following changes would cause the observed fringes to be more closely spaced?
- Reducing the separation between the slits
- Using blue light instead of green light
- Used red light instead of green light
- Moving the light source further away from the slits.
The correct answer is: Using blue light instead of green light
Related Questions to study
physics-
Radio waves coming at 
to vertical are received by a radar after reflection from a nearby water surface & directly. What should be height of antenna from water surface so that it records a maximum intensity. (wavelength = 
).
Radio waves coming at to vertical are received by a radar after reflection from a nearby water surface & directly. What should be height of antenna from water surface so that it records a maximum intensity. (wavelength = ).
physics-General
physics-
The figure shows a transparent slab of length 1m placed in air whose refractive index in x direction varies as 
The optical path length of ray R will be
The figure shows a transparent slab of length 1m placed in air whose refractive index in x direction varies as The optical path length of ray R will be
physics-General
physics-
In the YDSE shown the two slits are covered with thin sheets having thickness t & 2t and refractive index 2m and m. Find the position (y) of central maxima
In the YDSE shown the two slits are covered with thin sheets having thickness t & 2t and refractive index 2m and m. Find the position (y) of central maxima
physics-General
physics-
Young’s double slit experiment is carried with two thin sheets of thickness 10.4 mm each and refractive index m1= 1.52 and m2 = 1.40 covering the slits S1 and S2 , respectively. If white light of range 400 nm to 780 nm is used then which wavelength will form maxima exactly at point O, the centre of the screen ?
Young’s double slit experiment is carried with two thin sheets of thickness 10.4 mm each and refractive index m1= 1.52 and m2 = 1.40 covering the slits S1 and S2 , respectively. If white light of range 400 nm to 780 nm is used then which wavelength will form maxima exactly at point O, the centre of the screen ?
physics-General
physics-
In a YDSE experiment if a slab whose refractive index can be varied is placed in front of one of the slits then the variation of resultant intensity at mid-point of screen with 
will be best represented by 
.[Assume slits of equal width and there is no absorption by slab]
In a YDSE experiment if a slab whose refractive index can be varied is placed in front of one of the slits then the variation of resultant intensity at mid-point of screen with will be best represented by .[Assume slits of equal width and there is no absorption by slab]
physics-General
physics-
The figure shows a transparent slab of length 1m placed in air whose refractive index in x direction varies as The optical path length of ray R will be
The figure shows a transparent slab of length 1m placed in air whose refractive index in x direction varies as The optical path length of ray R will be
physics-General
physics-
In the YDSE shown the two slits are covered with thin sheets having thickness t & 2t and refractive index 2m and m. Find the position (y) of central maxima
In the YDSE shown the two slits are covered with thin sheets having thickness t & 2t and refractive index 2m and m. Find the position (y) of central maxima
physics-General
physics-
Young’s double slit experiment is carried with two thin sheets of thickness 10.4 mm each and refractive index m1= 1.52 and m2 = 1.40 covering the slits S1 and S2 , respectively. If white light of range 400 nm to 780 nm is used then which wavelength will form maxima exactly at point O, the centre of the screen ?
Young’s double slit experiment is carried with two thin sheets of thickness 10.4 mm each and refractive index m1= 1.52 and m2 = 1.40 covering the slits S1 and S2 , respectively. If white light of range 400 nm to 780 nm is used then which wavelength will form maxima exactly at point O, the centre of the screen ?
physics-General
physics-
A hollow sphere of mass M and radius r is immersed in a tank of water 
The sphere would float if it were set free. The sphere is tied to the bottom of the tank by two wires which makes angle 45° with the horizontal as shown in the figure. The tension 
in the wire is :
A hollow sphere of mass M and radius r is immersed in a tank of water The sphere would float if it were set free. The sphere is tied to the bottom of the tank by two wires which makes angle 45° with the horizontal as shown in the figure. The tension in the wire is :
physics-General
physics-
A dumbbell is placed in water of density 
. It is observed that by attaching a mass m to the rod, the dumbbell floats with the rod horizontal on the surface of water and each sphere exactly half submerged as shown in the figure. The volume of the mass m is negligible. The value of length l is
A dumbbell is placed in water of density . It is observed that by attaching a mass m to the rod, the dumbbell floats with the rod horizontal on the surface of water and each sphere exactly half submerged as shown in the figure. The volume of the mass m is negligible. The value of length l is
physics-General
physics-
A slender homogeneous rod of length 2L floats partly immersed in water, being supported by a string fastened to one of its ends, as shown. The specific gravity of the rod is 0.75. The length of rod that extends out of water is :
A slender homogeneous rod of length 2L floats partly immersed in water, being supported by a string fastened to one of its ends, as shown. The specific gravity of the rod is 0.75. The length of rod that extends out of water is :
physics-General
physics-
An open-ended U-tube of uniform cross-sectional area contains water (density 
standing initially 20 centimeters from the bottom in each arm. An immiscible liquid of density 4.0 grams/ 
is added to one arm until a layer 5 centimeters high forms, as shown in the figure above. What is the 
of the heights of the liquid in the two arms?
An open-ended U-tube of uniform cross-sectional area contains water (density standing initially 20 centimeters from the bottom in each arm. An immiscible liquid of density 4.0 grams/ is added to one arm until a layer 5 centimeters high forms, as shown in the figure above. What is the of the heights of the liquid in the two arms?
physics-General
physics-
A light semi cylindrical gate of radius R is piovted at its mid point O, of the diameter as shown in the figure holding liquid of density r. The force F required to prevent the rotation of the gate is equal to
A light semi cylindrical gate of radius R is piovted at its mid point O, of the diameter as shown in the figure holding liquid of density r. The force F required to prevent the rotation of the gate is equal to
physics-General
physics-
In the figure shown, the heavy cylinder (radius R) resting on a smooth surface separates two liquids of densities and 
. The height ‘h’ for the equilibrium of cylinder must be
In the figure shown, the heavy cylinder (radius R) resting on a smooth surface separates two liquids of densities and . The height ‘h’ for the equilibrium of cylinder must be
physics-General
physics-
A U – tube having horizontal arm of length 20 cm, has uniform cross-sectional area 
It is filled with water of volume 60 cc. What volume of a liquid of density 4 g/cc should be poured from one side into the U – tube so that no water is left in the horizontal arm of the tube?
A U – tube having horizontal arm of length 20 cm, has uniform cross-sectional area It is filled with water of volume 60 cc. What volume of a liquid of density 4 g/cc should be poured from one side into the U – tube so that no water is left in the horizontal arm of the tube?
physics-General
